Carbon Dioxide-Assisted Oxidative Dehydrogenation of Propane in the Presence of Chromium Oxide Catalysts in the Gas Phase and under Supercritical Conditions: Effect of Support and Process Parameters

The paper describes the synthesis and characterization of a set of chromium oxide catalyst systems that contain 5 wt % of chromium and are supported on various commercial supports: 5Cr/SiO2, 5Cr/Al2O3, 5Cr/Al2O3(Si), 5Cr/Al2O3(Ca,Mg), 5Cr/Al2O3(Si,Na), 5Cr/TiO2, 5Cr/ZrO2(W), 5Cr/ZrO2(Si), and 5Cr/ZrO2(La). The catalyst systems are studied by XRD, UV–Vis diffuse reflectance spectroscopy, and SEM–EPMA methods; all the samples are tested in the CO2-assisted oxidative dehydrogenation of propane. The catalyst system exhibiting the highest activity in the propane dehydrogenation reaction in the presence of CO2 in the gas phase is studied under supercritical conditions. The prospects for using high pressure in the studied reaction are shown.